Lost in the shuffle of the James Comey firing last week was the indignant resignation of another department head: John H. Thompson, director of the Census Bureau.

It might be easy to dismiss a department that performs its core function just once every 10 years — until, that is, the full scope of our decennial counting sets in.

The Census gets its own department because it’s major: We allocate Congressional seats and Electoral College votes based on this number, earmark resources for roads, schools and other public works. Our state, county and city districts are drawn with these numbers in mind. And corporations rely on them for insight into investments like grocery stores, apartment buildings and professional sports franchises.

Not that it’s perfect, nor does it claim to be. Subsequent measures showed the 2010 Census came up short on African-Americans, renters and young males and overcounted the total population by about 36,000 people out of 325 million. And really, there’s no perfect way to quantify the undocumented residents of the country, though the Census makes a valiant effort. But we all should agree that this is our best effort.

Thompson has said that the current methodology, which includes utilizing land-line accounts and other outmoded technological means, is inadequate to the task. Budget funds were scarce for a digital data-collection system, the cost of which jumped this year by about a third, to $965 million. Rather than fight with the new regime, he split.

When a guy like Thompson, who has been with the department for more than 30 years — four of them as director — walks off the job, we should all be concerned. Especially since appointing positions does not seem to be a priority these days.

Just a few years ago — a few months ago — the idea of the federal government dropping the ball on something as basic as this would have been inconceivable.

But in Trump’s America, even the head count is up for negotiation.